Air-preheating device



7 Nov. 11, 1930. J. RYDMARK ,7 ,3

AIR PREHEATING DEVICE Filed Feb. 1 19 2 Sheets-Sheet 1 IN VEN TOR M W irrors/wa s Nov. 11, 1930. J. RYDMARK 1,781,303

AIR PREHEATING DEVICE Filed Feb. 1 192 2 Sheets-Sheet 2 IN VEN TOR WZTTORNEYS' Patented Nov. 11, 1930 UNITED STATES PATENT OFFICE JOSEE RYDMARK, OF NEW ROCHELLE, NEW YORK, ASSIGNOR TO INTERNATIONAL COM- BUSTION ENGINEERING CORPORATION,

DELAWARE OF NEW YORK, N. Y., A CORPORATION OF AIR-PBEHEATING DEVICE Application filed February This invention relates to air heaters and more particularly to those of the regenerative type and is especially useful in connection with that class of pulverized fuel burning IT equipment in which the combustion chamber is largely defined by boiler surfaces subject to radiant heat. In such installations it is required to highly preheat the combustion air to increase the furnace temperature head in order to obtain proper combustion and it is thru the practice of my invention that highly preheated air is secured.

Air preheaters of the regenerative type have heretofore been employed but these are of expensive and rather cumbersome construction. In these heaters the heating or regenerative elements are rotated with respect to the gas and air inlets and outlets.

I propose to provide a novel arrangement of the inlets and outlets of the gas and air a with respect to the regenerative elements,

whereby it is unnecessary to rotate either the inlet or outlet with respect to the regenerative elements or the regenerative elements with respect to the inlets and outlets. The

arrangement of inlets and outlets and the regenerative elements is such, in accordance with my invention, that I can use rotatable blanking elements which are of very light construction and which can be operated with but a minimum of power as compared to that required to rotate the regenerative elements for example.

Among other objects of my invention, therefore, is the provision of a heater of the above character which is compact, inexpensive to manufacture, easily assembled, easily taken apart and eflicient in o eration.

Other more specific o jects and advanta es will appear hereinafter in the specification of the preferred form of my invention illustrated in the accompanying drawings, wherein Fig. 1 is a longitudinal sectional view thru the heater, certain of the parts appearing in elevation;

Fig. 2 is a reduced plan section taken substantially on the line 22 of Fig. 1 in which only certain of the heating elements appear diagrammatically 1, 1926. Serial No. 85,078.

Fig. 3 is a section taken on the line 3-3 of F1g. 1, certain of the heating elements appearmg n diagrammatic view;

1g. 4 is an enlarged elevationalview of one of the heating elements, certain portions being broken out to condense the figure; and

Fig. 5 is a plan view of Fig. 4.

Referring to the drawings and more'particularly to Fig. 1 the device comprises a tubular casing A, the lower end of which constitutes a gas inlet 4, the upper end a gas outlet 5 and the intermediate portion houses the regenerative or heating elements B. Adjacent the upper end of the casing A I have provided an annular compartment 6 constituting an air inlet and adjacent the lower end an annular compartment '7 constituting an air outlet. These gas and air inlets and outlets are continually in communication with the interior of the casing, and in the absence of the blanking means new to be described both gas and air could flow thru all portions of the casmg.

The blanking means 8 and 9 each comprise a member substantially tubular in form and of a diameter to fit the casing A with a slight running clearance. A diagonal plate 10 which may, as shown, he formed integral with the tubular member extends inwardly from the periphery of the tubular member approximately to a line cutting the centre thereof. In other words this plate is half moon shaped in consequence of which the gas inlet and gas outlet are separated from the air inlet and air outlet. These members are secured to the vertically extending shaft 12 in any suitable manner which shaft is adapted to be rotated by any suitable form of driving device 13, the upper member 8 be ing positioned with its full open end up and the lower member 9 with its full open end down. The very light constructon of these rotatable members enables me to employ a comparatively small and inexpensive driving device as the power requirements are little.

From what has been said it is apparent that one half of the intermediate portion of the casing is always open to gas flow and the other half is always open to air flow.

Referring now to the intermediate per tubular casing A and to the central tube in any suitable manner as by welding. A plurality of radiall disposed loosely set in, i. e., readily remova le, regenerative elements 16 are provided in each of the segmental compartments between adjacent ones of which I provide radially disposed loosely set in plates 17 acting as positioners. These elements and the loose plates are prevented from falling thru the heater as by means of annular shelflike portions 18 and 19 on the casing A and tube 15 res ectively.

Each radially disposed regenerative element 16 comprises a plurality of spaced plates 20 which plates increase in width in groups as clearly shown in Fig. 5, that is to say, the plates at the centre of the heater are narrower than the plates at the periphery of the heater thus providing an element of substantially segmental shape. In the present instance I have shown each group of three plates of the same width whereby the number of various sized plates which would have to be used in the making of the heater is minimized. It is to be understood that the number of plates comprising'a group may vary in accordance with the size of the heater. These plates are held in assembled relation as by means of the rods 21 and the spacer bushings 22.

It will be seen that as the blanking elements are rotated passages thru the intermediate section formed by the regenerative elements are successively converted from gas passage to air passage, one half of the number of regenerative elements being always exposed to air and the other half to gas.

In order to prevent leakage of gas and air I have associated sealing means with the blanking meanscomprisingannular members 23 and 24 secured to the inside of the casing A and overlapping the edges of the open ends of the blanking means, and annular members 25 and 26 secured to the circular portions of the other ends thereof which overlap the portions 27 and 28 respectively of the casing A within the annular compartments 6 and 7. Thus leakage is minimized at these points due to the restricted and tortuous path which any gas or air must take in leaking. The diagonally extending plates 10, 10 of the members or blanking means 8 and 9 are provided at their edges adjacent the regenerative elements B with aprons 29, 29 for preventing leakage at this point.

Referring to Fig. 1 it will be seen that I have provided a byass 30 between the gas inlet and outlet for yassing a portion of the gases being supplie to the heater. This may be accomplished by manipulation of the dampers 31, 32 and 33.

vA soot blower is indicated at 34 thru the medium of which steam may be blown over the elements for the purpose of cleaning the heater. 7 What I claim is:

In an air heater of the regenerative type, a tubular casing, a plurality of fixed plates dividing said easing into segmental compartments, a plurality of radially disposed loose heating, elements in each compartment and loosely positioned nests of plates between adjacent elements, said nests each inclu a plurality of spaced plates increasing in wi th from the center to the periphery of the easing.

In testimony whereof, I have hereunto signed my name. v

JOSEF RYDMABK. 

